Apparatus for storing liquids



June 16, 1931. w ggms 1,810,741

APR ARATUS FOR STORING LIQUIDS Filed May 2, 1927 ,Mmae%% HTTOPA/EK' Patented June 16, 1931 PATENT OFFICE JOHN H. WIGGINS, OF BABTLESVILLE, OKLAHOMA APPARATUS FOR STORING LIQUIDS Application flied May 2,

This invention relates to the art of storing large quantities of liquids which are of such a nature that they expand and contract, due

to variations in temperature, or in atmos-.

i pheric or climatic conditions.

One object of my invention is to provide an apparatus for storing volatile liquids, that reduces the fire hazard to a minimum, eliminates evaporation and prevents corrosion of the tanks or containers in which the liquids are stored.

Anotherobject of my invention is to provide an apparatus for storing volatile liquids that overcomes the necessity of using a layer of secondary liquid underneath the liquid that is being stored, which secondary liquid may be varied as to volume in order to maintain the level of the liquid stored at or near a constant height.

And still another object is to provide an apparatus for storing volatile liquids that overcomes the necessity of equipping liquid storage tanks with vent valves that work at low differential pressures.

And still another object of my invention is to provide a liquid storage apparatus of novel construction.

My improved apparatus is adapted for use in the storage of gasoline, crude petroleum and various other kinds of liquids that are highly volatile and inflammable, and it is particularly adapted for storing volatile and inflammable liquids which contain substances that produce corrosion of metal in the presence of air, such, for example, as crude petroleum of high sulphur content.

Figures 1, 2, 3 and 4: of the drawings are vertical sectional views, illustrating diagrammatically, the operation of one formof apparatus embodying my invention; and

Figure 5 is a top plan view of said apparatus..

In the drawings A designates one or more large storage tanks, preferably tanks of the type that comprise a side wall 1 and a metal top or roof 2 connected at its peripheral edge by a gas-tight joint to the upper edge of said side wall and constructed in such a way that it is capable of flexing or moving upwardly and downwardly when the liquid in said tank Serial No. 188,387.

expands and contracts, B designates an auxiliary storage tank, preferably of the type in which the closure for the upper end of the tank is formed by a floating deck 3 that rests upon and is supported by the liquid in the 555 tank, and an expansible and contractible shoe 4 arranged in sliding engagement with the side wall of the tank and attached by a substantially gas-tight flexible element 5 to an upwardly-projecting rim 5* on the floating deck 3, C designates overflow pipes that lead from the main tanks A to the auxiliary storage tank B, D designates a pump of any suitable kind that is used to withdraw the liquid from the auxiliary tank B through an outlet pipe D and force it back into the main storage tanks A through return pipes D and E designates manually-operable valves in the pipes D and D for controlling the flow of the liquid through said pipes.

The flexible roof 2 of each of the main storage'tanks A is provided with a vent 6, and the overflow pipes C that lead from the tanks A are equipped with vents 7 and are constructed so that the overflow points 8 of said pipes are located at a point higher than the top edge of the side walls of the tanks A. It is immaterial whether the apparatus comprises one or a plurality of main storage tanks A, and the particular construction of said'tanks is immaterial, but I prefer to use tanks A of the general type described in my pending application for Patent Serial No. 132,540, filed August 30, 1926.

As to the auxiliary storage tank B, this may be a tank of the general type described in various prior patents granted to me, for example, U. S. Patent No. 1,574,013, dated February 23, 1926.

The operation of the apparatus shown in 0 the drawings is substantially as follows: Assume that the season of the year is winter or early spring when the liquid in storage will constantly grow warmer for several months. The liquid to be stored is pumped into the 5 empty tank or tanks A shown in Figure 1 until the liquid surface is just above the top edges of the side walls of said tanks, the pressure that the liquid exerts on the roofs 2 of said tanks causing them to flex upwardly into the position shown in Figure 2. Due to the fact that the roofs are provided with vents 6, air and gases will escape from the tanks A during the operation of filling them with liquid, and at the completion of the filling operation the liquid in each of the main tanks A will be in direct contact with the underside of the roof 2 of said tank. As the season progresses the liquid in the tanks A warms up and expands, thereby causing the roofs 2 of said tanks to flex upwardly until they reach the position shown in Figure 3, the degree of upward flexing or upward movement of the roofs 2 being determined by the height of the overflow points 8 of the overflow pipes C that lead from the tanks A. If the liquid in the tanks A expands still more, then some of the liquid will escape through the overflow pipes C. If the apparatus comprises an auxiliary storage tank 13, as shown in Figure 4, the escaping liquid will gravitate onto said auxiliary storage tank. The increased volume attained by the upward flexing of the roofs 2 of the main tanks A, plus the capacity of the auxiliary tank B preferably should be more than the total expected increase of liquid volume. As the season progresses and the liquid cools and contracts, the roofs 2 of the main tanks A will flex downwardly or lower until they reach substantially the position shown in Figure 2. At this time, or somewhat sooner, if desired, liquid of the same kind is pumped*back into the main tanks A, so as to insure the tanks A containing suflicient liquid to cause the underside of the roofs 2 of said tanks to remain in direct contact with the liquid. In an apparatus of the particular kind herein illustrated this is accomplished by opening the valves E and setting the pump D in operation so as to withdraw liquid from the auxiliary tank B and force said liquid into the main tanks A.

With the exception of pumping liquid of the same kind .into the main tanks A, which operation is preferably done under supervision once a year, the above-described method of storing volatile liquids requires practically no attention, for after the tanks A have been filled, the flexing or movement of the roofs 2 of said tanks takes care of the expansion and contraction of the liquid. As previously stated, it is preferable to equip the apparatus with an auxiliary storage tank, B, as herein shown, so as to provide for the expansion of liquids that increase greatly in volume when subjected to temperatures as high as those reached in the summer months, but if the liquid that is being stored is of such a nature that it has a relatively slight expansion, for example, 1% of 25 F., it is highly practicable to simply store such liquid in a tank of the kind represented by one of the tanks A of the apparatus herein illustrated and take care of the entire thermal expansion of the liquid by the u ward and downward flexing of the roof of t e tank.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An apparatus for storing volatile liquids, comprising a main tank provided with a metallic top connected at its peripheral edge to the side wall of said tank and constructed so that it is capable of flexing to provide for the expansion and contraction of the liquid in said tank, an auxiliary storage tank, a conduit leading from said main tank to said auxiliary tank and provided with an overflow point located at a point higher than the top edge of the side wall of said main tank, a vent for said main tank, a vent for said overflow conduit, and means for returning liquid from the auxiliary tank to the main. tank.

2. An apparatus for storing volatile hquids, comprising atank provided with a metal roof constructed so that it is adapted to be flexed upwardly and downwardly by the liquid in the tank which exerts pressure on the underside of said roof when said liquid expands and contracts, a vent in said roof, means for permitting the volatile liquid to escape from said tank during periods of the year when an abnormal expansion of the liquid is liable to occur, at a rate such as to prevent the roof from being strained by the upward pressure which the confined liquid exerts on same, and means for feeding volatile liquid of the same kind into the tank so as to maintain a body of liquid in the tank that covers the under side of the roof.

JOHN H. wreerus. 

